Why the United States Drives on the Right, Not the Left

The United States drives on the right because early American freight wagons put drivers on the left, prompting practical “keep right” customs that states codified from the late 1700s onward; the rise of left-hand–steering automobiles in the early 20th century then cemented the practice. Cultural distance from Britain and continental (especially French) influence reinforced the shift, but the decisive forces were ergonomics, state law, and automotive standardization.

Historical Roots: From British Left to American Right

Britain’s left-side custom traces back to premodern travel and sword-carrying norms, which favored passing on the left. American colonies initially used mixed practices, with no uniform rule. After independence, however, the young United States diverged from Britain. The change was less about symbolism than about how Americans actually moved goods: big wagons, long teams of horses, and drivers positioned for control and visibility.

The Wagon Era and a Practical Reason to “Keep Right”

In the 18th and early 19th centuries, American freight moved on large wagons such as the Conestoga. These wagons often lacked a driver’s seat; teamsters typically rode the left-rear horse or stood on the left side to keep their dominant right hand free for the whip. From that position, keeping to the right side of the road provided a better view of oncoming traffic and made it easier to judge the space when wagon wheels passed close at the center of the road.

How Laws Locked the Habit In

What began as a practical custom soon became law. States, not the federal government, set traffic rules in the United States, and they began mandating right-side travel shortly after independence, especially as turnpikes and intercity roads multiplied.

The following timeline highlights key legal milestones and standardization moments that fixed right-side driving in the U.S.

1. 1792: Pennsylvania’s charter for the Philadelphia and Lancaster Turnpike required keeping to the right, a widely cited early U.S. “keep right” rule.
2. Early 1800s: New York (1804) and other states passed right-side statutes as turnpike building accelerated.
3. Mid–late 19th century: Right-side driving spread nationwide through state-by-state laws and enforcement on stage routes and city streets.
4. 1900s–1910s: Automobiles proliferated; states harmonized road rules to accommodate interstate travel.
5. 1908 onward: The Ford Model T popularized left-hand steering, reinforcing right-side traffic; other U.S. makers followed.

By the early 20th century, the combination of state statutes and vehicle design made right-side driving universal across the United States.

Automobiles Finished the Job

Early American automobiles experimented with steering position—some had right-hand steering—but mass-market leaders changed the equation. Henry Ford’s Model T (1908) standardized the left-hand steering wheel for better alignment with right-side traffic: the driver sat closer to the center line, easing overtaking and visibility. As Ford’s production scaled, left-hand steering became the American norm, further entrenching right-side driving.

Other Influences—And What Didn’t Matter as Much

Several additional factors nudged the United States toward right-side travel, but some popular explanations are overstated. The French Revolution and Napoleonic-era Europe spread right-side customs on the continent, and America’s links with continental engineering and road culture made right-hand norms familiar. Meanwhile, distancing from British traditions after independence may have carried symbolic weight, but the day-to-day logic of wagon handling and state law were more decisive.

Key influences at a glance

These were the main forces that pushed the U.S. to the right-hand side of the road and kept it there.

• Wagon ergonomics: Drivers positioned on the left preferred right-side travel for visibility and control.
• State legislation: From the 1790s onward, states codified “keep right,” creating legal consistency.
• Continental precedent: Right-side customs in France and elsewhere aligned with emerging U.S. practice.
• Automotive design: Left-hand steering, especially after the Model T, made right-side driving the practical default.
• National uniformity: Interstate commerce and motoring demanded consistent rules across state lines.

Together, these influences formed a self-reinforcing system: practice shaped law, and law guided design, which in turn hardened practice into a uniform national standard.

Why Not Switch Now?

Changing sides is technically possible—several countries have switched—but it is enormously costly and disruptive in a nation as vast and motor-dependent as the United States. Road engineering, signage, vehicle fleets, intersections, freeway interchanges, driver education, and cross-border consistency with Canada and Mexico all align to the right. With no compelling safety or economic advantage to change, the status quo prevails.

Bottom Line

The United States doesn’t drive on the left because early American freight practices favored keeping right, states codified that custom beginning in the late 18th century, and the automobile era—especially left-hand steering—cemented it. Culture and continental influence played roles, but ergonomics and law did the heavy lifting.

Summary

America’s right-side driving grew from practical wagon-era habits into state law, then became irreversible when cars adopted left-hand steering. While Britain and many former British territories retained left-side traditions, the U.S. aligned with right-hand continental norms early on, and modern infrastructure makes any reversal both unnecessary and prohibitive.

Why does China drive on the right?

China drives on the right because the American-backed Nationalist government of Chiang Kai-shek ordered the switch from left-hand traffic to right-hand traffic in 1946, influencing the country to align with the practices of continental Europe and the United States rather than British colonial traditions seen in Hong Kong. This decision was influenced by American advisors and reflected a broader trend of countries adopting right-hand traffic as their own influence grew in the 20th century. 
Historical context and the switch to the right

• Early Practices: In the early 20th century, China lacked a uniform driving rule, with some areas, like Shanghai and Beijing, driving on the left. 
• The Nationalist Government’s Decision (1946): The ruling Nationalist Party, led by Chiang Kai-shek, mandated a nationwide switch from left-hand to right-hand traffic. 
• American Influence: This switch was likely influenced by American advisors, aligning China with the growing global influence of the United States and its adoption of right-hand traffic. 
• Alignment with Europe: France had established right-hand traffic as the norm during the Napoleonic era, and this practice spread throughout Europe and its colonies. 
• Divergence from Hong Kong: This 1946 decision did not extend to Hong Kong, which was a British colony and continued to drive on the left to maintain its connection with the United Kingdom’s traffic practices. 

Consequences of the 1946 Switch

• Hong Kong’s Anomaly: The switch in mainland China led to a divergence with Hong Kong’s driving side, a situation that persists today, though efforts have been made to allow cross-border travel. 
• Logistical Challenges: The decision created logistical hurdles for cross-border travel, as vehicles must adapt to different driving sides when moving between mainland China and Hong Kong. 

Why do Americans drive on the right not left?

New York, in 1804, became the first State to prescribe right hand travel on all public highways. By the Civil War, right hand travel was followed in every State. Drivers tended to sit on the right so they could ensure their buggy, wagon, or other vehicle didn’t run into a roadside ditch.

Why is the British drive on the left side?

The practice of driving on the left side of the road in Britain dates back to the late 18th century. The tradition is believed to have originated from the need for horse riders to keep their right hand free for greeting or defending against oncoming traffic.

Why does the UK drive on the left and the US on the right?

England (and the UK) drives on the left due to a long-standing tradition rooted in the need for right-handed riders and drivers to keep their sword or whip hands free for defense and control, which also made it safer to mount horses from the left. The United States adopted driving on the right because its dominant 18th-century transport involved large, heavy wagons and teams of horses, where the driver would sit on the left horse to control the team and avoid collisions, leading to a tradition of right-hand driving that predated Britain’s formal left-hand law.
 
Driving on the Left (England/UK)

• Pre-Automotive Era: Historically, most people are right-handed. For riders and knights, keeping to the left side of the road allowed their right hand, their dominant and sword hand, to be free to defend against potential attackers. 
• Mounting/Dismounting: It was safer to mount and dismount a horse from the left side of the road, which was the left-hand traffic side, rather than the middle of the road. 
• Official Adoption: Britain formalized this practice, making left-hand traffic the law in the 18th century, which was later reinforced by the Highway Act of 1835. 

Driving on the Right (United States)

• Post-Colonial Transition: After gaining independence, the US had a growing opposition to Old World customs and the British system of left-hand traffic. 
• Wagon and Horse Teams: The dominant form of long-distance transport in the US involved large, multi-horse wagons. Drivers would sit on the left-hand horse, often the rearmost of a team, to keep their right whip hand free to control the animals. 
• Safety and Practicality: Driving on the right allowed drivers to better judge the clearance between passing wagons, as they were seated to the left of the team, near the center of the road. 
• Dominant Practice: This practical shift in the US, driven by large freight wagons, established a tradition of right-hand driving that was distinct from Britain’s.